Re: [PATCH 1/2] nvme: make independent ns identify default

[Christoph Hellwig]

On Wed, Oct 09, 2024 at 08:56:32AM -0600, Keith Busch wrote:
> On Wed, Oct 09, 2024 at 09:46:11AM +0200, Christoph Hellwig wrote:
> > On Tue, Oct 08, 2024 at 04:55:02PM +0200, Matias Bjørling wrote:
> > > However, the independent namespace data structure
> > > is mandatory for devices that implement features from the 2.0+
> > > specification. Therefore, we can check this data structure first. If
> > > unavailable, retrieve the generic attributes from the NVM command set
> > > identify namespace data structure.
> > 
> > I'm not a huge fan of this.  For pre-2.0 controllers this means
> > we'll now send a command that will fail most of them time.  And for
> > all the cheap low-end consumer device I'm actually worried that they'll
> > get it wrong and break something.
> 
> We already send identify commands that we expect may break on pre-2.0
> controllers: the Identify NS Descriptor List.

Identify NS Descriptor List is mandatory starting with NVMe 1.3.  We only
issue it for 1.3 or if the controller advertises supporting multiple
command sets.